Kamil Dudka wrote:
> Thanks! This also helps to suppress the false positives on cryptsetup
> with Coverity Static Analysis version 2019.03.
Good! Since this is the approach that Paul prefers, I'm pushing this one:
2019-05-10 Bruno Haible <br...@clisp.org>
base64: Avoid false positive warning from Coverity.
Reported by Kamil Dudka <kdu...@redhat.com>.
Idea by Paul Eggert.
* lib/base64.c (base64_encode_fast, base64_encode): Add a no-op
'& 0x3f' to the array index expressions. This convinces Coverity that
there is no out-of-bounds array reference, regardless of the input.
diff --git a/lib/base64.c b/lib/base64.c
index f3f7298..a00e0f4 100644
--- a/lib/base64.c
+++ b/lib/base64.c
@@ -70,7 +70,7 @@ base64_encode_fast (const char *restrict in, size_t inlen,
char *restrict out)
{
while (inlen)
{
- *out++ = b64c[to_uchar (in[0]) >> 2];
+ *out++ = b64c[(to_uchar (in[0]) >> 2) & 0x3f];
*out++ = b64c[((to_uchar (in[0]) << 4) + (to_uchar (in[1]) >> 4)) &
0x3f];
*out++ = b64c[((to_uchar (in[1]) << 2) + (to_uchar (in[2]) >> 6)) &
0x3f];
*out++ = b64c[to_uchar (in[2]) & 0x3f];
@@ -103,7 +103,7 @@ base64_encode (const char *restrict in, size_t inlen,
while (inlen && outlen)
{
- *out++ = b64c[to_uchar (in[0]) >> 2];
+ *out++ = b64c[(to_uchar (in[0]) >> 2) & 0x3f];
if (!--outlen)
break;
*out++ = b64c[((to_uchar (in[0]) << 4)
